Radiator not heating up!!!

Hi,Radiator in living room is not heating up properly. The system is working fine in general but when I turn on living room rad the hot water only barely enters the rad. If I feel about an inch into the rad near the thermostatic valve I can feel its perfectly hot but it'ls not travelling across the rad. After about an hour this heat will only marginally creep across the rad. I'm happy that the thermostatic valve is opening and working fine and I've never had a problem with sludge. Could the lock shield valve be jammed shut? I've opened it fully and gave it a few bangs but the pipe out of the rad the far side of the valve remains cold and never warms up as if the water can not get out of the rad. I should say the rad is in a room that is not normally used so is only turned on very occasionally. Can this occur even though the lock shield valve feels normal and free when turning - has anyone come across this before and is only solution to drain system and replace valve.


Thanks in advance,
Maddad

Assuming there isn't air in the rad thats causing the issue would you consider taking off the radiator & checking to make sure it's "sludge free"? Garden hose in one side, let water run through it.

Replacing the valves, means a drain down on your system, which has added fun depending on the heating system you have in place.

Are all other rads working as expected? Where is this rad in relation to the burner i.e. last in the circuit? Is the pump ok?

try opening the lockshield valve half a turn, on the other end of the radiator

I'd bleed the radiator before I did anything else; assuming, that is, that the valve at the other end is open as roker suggested.

Note the lockshield valve should not be fully open, only if it is at the furthest point, it is used to balance the system so that all rads get the same flow

I had a similar issue myself 2 weeks back with 2 rads.
I managed to re-balance the system myself (after some googling) and all working fine now.

Link here if you've tried bleeding etc..

http://www.diydoctor.org.uk/projects/balancingcentralheatingsystems.htm

Good luck.

Hi,

Thanks - got problem sorted. I believe it was dirt in the lockshield valve as continued and repeated turning on and off of the valve seems to have sorted the problem and the rad is heating up as normal again.




Thanks all,
Maddad